renderer: asynchronously load background tex (#11749)

Bumps required hyprgraphics to 0.1.6

---------

Co-authored-by: Mihai Fufezan <mihai@fufexan.net>

src/helpers/MainLoopExecutor.cpp

@@ -0,0 +1,47 @@
+#include "MainLoopExecutor.hpp"
+#include "../managers/eventLoop/EventLoopManager.hpp"
+#include "../macros.hpp"
+
+static int onDataRead(int fd, uint32_t mask, void* data) {
+    ((CMainLoopExecutor*)data)->onFired();
+    return 0;
+}
+
+CMainLoopExecutor::CMainLoopExecutor(std::function<void()>&& callback) : m_fn(std::move(callback)) {
+
+    int fds[2];
+    pipe(fds);
+
+    RASSERT(fds[0] != 0, "CMainLoopExecutor: failed to open a pipe");
+    RASSERT(fds[1] != 0, "CMainLoopExecutor: failed to open a pipe");
+
+    m_event = wl_event_loop_add_fd(g_pEventLoopManager->m_wayland.loop, fds[0], WL_EVENT_READABLE, ::onDataRead, this);
+
+    m_readFd  = Hyprutils::OS::CFileDescriptor(fds[0]);
+    m_writeFd = Hyprutils::OS::CFileDescriptor(fds[1]);
+}
+
+CMainLoopExecutor::~CMainLoopExecutor() {
+    if (m_event) // FIXME: potential race in case of a weird destroy on a worker thread
+        wl_event_source_remove(m_event);
+}
+
+void CMainLoopExecutor::signal() {
+    const char* amogus = "h";
+    write(m_writeFd.get(), amogus, 1);
+}
+
+void CMainLoopExecutor::onFired() {
+    if (!m_fn)
+        return;
+
+    m_fn();
+    m_fn = nullptr;
+
+    // we need to remove the event here because we're on the main thread
+    wl_event_source_remove(m_event);
+    m_event = nullptr;
+
+    m_readFd.reset();
+    m_writeFd.reset();
+}